Immunoglobulin (Gm) allotype frequencies in idiopathic membranous nephropathy and minimal change nephropathy.

40 Caucasoid patients with idiopathic membranous nephropathy (IMN) and 49 Caucasoid patients with minimal change nephropathy (MCN) were immunoglobulin allotyped for the Gm markers G1m (1, 2, 3) and G3m (5, 11, 21). Compared with normal controls the IMN group had a significantly decreased incidence of the G1m (3); G3m (5, 11) phenotype (P = less than 0.005). This decrease was accompanied by concommitant increase in both the G1m (1, 3); G3m (5, 11, 21) and the G1m (1, 2, 3); G3m (5, 11, 21) phenotypes. The result was most pronounced in IMN patients with deteriorating renal function. In contrast no significant differences were observed between the Gm phenotype frequencies of the MCN patients and controls.